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AStructuredDecisionMakingFrameworktoEvaluateAlternativeBuckHarvestManagementStrategies
Deer hunters in New York State have diverse views about buck hunting. Although many hunters have voiced a
desire to reduce yearling (1.5 year old) buck take to have a greater chance of taking an older buck with larger
antlers, many hunters also prefer to have the freedom to choose which buck they harvest and to practice
restraint voluntarily.
Changing the way that hunters pursue and take bucks is not necessary for the health of New York’s deer herd,
but it might better satisfy hunter desires in some portions of the state. To help managers make informed
recommendations, the New York State Department of Environmental Conservation (DEC) developed a
systematic process to evaluate potential buck hunting strategies in a way that accounts for regional variation
in hunter values and the impacts of the strategies.
February 2016
MakingDecisionsforWhite‐tailedDeerBuckHuntinginNewYorkState
Our goal is to develop a
decision framework that
uses objective criteria to
evaluate alternative
strategies for reducing
harvest of yearling bucks
for different areas of New
York State. Photo: Dick Thomas
StructuredDecisionMaking(SDM):SDM is an organized way to identify and evaluate creative
options and make choices in complex decision situations. SDM
is designed to give insight to decision makers about how well
their objectives may be satisfied by alternative courses of action
and clarifies the trade‐offs that may exist between potential
actions. It is especially helpful when stakeholders have
conflicting ideas of how a resource should be managed. SDM
uses scientific evaluation of population biology and stakeholder
values to identify an outcome that may best balance competing
interests. We used SDM to evaluate alternative buck harvest
strategies and incorporate the biological and social aspects of
buck harvest management in New York State.
TheStepsofSDM:1. Define the Problem
2. Determine Objectives
3. Identify Alternative Management
Actions
4. Evaluate Consequences
(outcomes) of the Management
Actions
5. Evaluate Tradeoffs Among
Objectives
6. Decide and Take Action
Buck Harvest Management in New York 2
ARegion‐SpecificApproachtoBuckHarvestManagementSeven different Buck Management Zones (BMZs) were evaluated for optimal buck harvest strategies.
We analyzed ecological, deer harvest, and management data to identify
logical groupings of Wildlife Management Units (WMUs) as BMZs.
BMZs are the level at which hunter preferences were measured
and alternative buck harvest strategies were considered.
We decided in advance to delineate only
5‐7 BMZs. We wanted to strike a
balance between capturing important
regional differences in deer biology
and hunter desires and not
over‐complicating our deer
hunting regulations. Because of
varying season structures,
Southern Zone WMUs were
separated from Northern Zone
WMUs, and Northern Zone WMUs
were grouped into two BMZs based on where Deer Management Permits
(DMPs; antlerless tags) are used. Additionally, because of distinctions in season structure and management
authority, WMUs 1C (Suffolk County) and 3S (Westchester County) were treated as one BMZ.
We used land cover data (e.g., % forest and agriculture in each WMU), a winter severity index (average
number of days with >15” of snow in each WMU), a crop productivity index (based on soil characteristics), and
several deer population parameters (yearling antler beam diameter, mean fawn to doe ratio, buck kill per
square mile) to create groupings. We then considered the number of deer hunter survey responses we had
for each BMZ to ensure that each BMZ had enough responses to adequately represent hunter interests for
decision making.
Photo: Dick Thomas
Buck Harvest Management in New York 3
ObjectivesforBuckHarvestManagementinNewYork
1. Maximize hunter satisfaction
See/take a “big” (≥2.5 year old) buck
See/take “any” (≥1.5 year old) buck
See/take “any deer” (fawns, does,
bucks)
Hunting opportunity and simple
regulations (other satisfaction)
2. Minimize impact on DEC’s ability to
manage and monitor deer populations
3. Minimize management costs
AlternativeHarvestStrategies
No change
Actively promote voluntary antler restrictions
1‐buck bag limit (1 buck / hunter / year)
Shorten the regular firearms season by 1 week in the
Southern Zone and 2 weeks in the Northern Zone
Mandatory antler point restriction (Bow season
through the 1st week of regular firearms season)
Mandatory antler point restriction (All seasons)
Note: because of geographic differences in antler
growth, mandatory antler restrictions would be a 4‐
point on one side rule in the Lake Plains and a 3‐point
rule everywhere else.
Consequences/Outcomes
We evaluated how well each of the management alternatives would do at achieving each of the specified
objectives. We did this in a couple ways.
1. We created a population model to predict the outcomes of each of the potential management
alternatives on the population size, and the number of legally harvestable deer of each age and sex.
2. We surveyed a random sample of hunters throughout New York to determine the desired outcomes
of hunters, what aspects of hunting they value, and how important these aspects are. This helped
us to determine, for each region, the relative importance of the hunter satisfaction objectives.
3. DEC biologists and law enforcement officers described how each management alternative would
influence the ability to manage the population and the cost of management.
EvaluationofTradeoffs
Because buck harvest management is
primarily a social tool, we placed most
of the relative importance weight on
hunter satisfaction (75% of decision),
followed by population management
(15%), and management costs (10%).
For each management alternative, we
calculated a “score” to reflect the
degree to which each objective was
satisfied. Photo: Dick Thomas
Buck Harvest Management in New York 4
NextStepsforBuckHarvestManagementinNewYork
The SDM process identified No Change as the optimal buck management strategy in all BMZs, consistent with
the desire of a majority of hunters across the state to maintain freedom of choice in buck harvest. However,
in light of the desire of many hunters to see more older‐age bucks in the population, DEC plans to increase its
efforts statewide to encourage hunters to voluntarily pass up shots at younger, small‐antlered bucks.
Voluntary restraint from taking young bucks can be an effective way to increase the proportion of older‐age
bucks in the population. Many New York hunters are already practicing voluntary restraint, and their efforts
are making a difference. Hunters in New York are now taking more older‐age bucks than ever before – more
than half of all antlered bucks taken in 2014 were at least 2 years old, and the number of at least 3 year old
bucks taken in recent years is up about 30 percent compared to the early 2000s and up approximately 80
percent from the early 1990s. Similarly, other states have seen dramatic shifts in harvest toward older, larger‐
antlered bucks with active promotion of voluntary restraint by the state wildlife agency and partner
organizations. It is clear that hunter choices matter!
RelativeScoreofVariousBuckManagementStrategies(Highest score is the “optimal” strategy; top two highlighted for each zone)
Buck Management Zone
Adirondack Lake Plains
Mohawk Valley
North‐western
South‐eastern
Southern Tier
Suffolk/ Westchester
No Change 0.594 0.466 0.413 0.415 0.427 0.425 0.458
Voluntary Restraint 0.546 0.424 0.372 0.371 0.384 0.382 0.422
1‐Buck 0.517 0.392 0.338 0.339 0.344 0.351 0.372
Shorter Season 0.577 0.380 0.320 0.386 0.331 0.333
MARs (partial season)
0.270 0.225 0.221 0.234 0.197 0.223
MARs (full season) 0.463 0.340 0.364 0.370 0.402 0.371 0.329
Photo: John Major
Buck Harvest Management in New York 5
HunterSurveyHighlights
Surveys were mailed to a random sample of 7,000 deer hunters statewide
to obtain specific information needed for the SDM process. Approximately
40% of surveys were returned, which was sufficient to provide statistically
reliable results for each Buck Management Zone.
Many hunters are satisfied with their opportunities in New York:
58% were moderately or very satisfied with current buck hunting rules.
41% were satisfied with their opportunity to take a large‐antlered buck,but 25% were dissatisfied; the rest were undecided.
HOWEVER, hunters have conflicting values about buck hunting:
Statewide, 57% greatly value their freedom to choose what type of buck to harvest, but 55% greatly
value a better chance to take a big, older buck.
Among Buck Management Zones, 43‐53% of hunters said that reducing harvest of young bucks was
important or very important, while 29‐37% said it was of low or no importance.
40‐54% expressed high or very high willingness to accept limitations on their freedom of choice to
achieve a reduction in harvest of young bucks; 30‐46% had low or no willingness to accept restrictions.
About 33% of hunters were primarily interested in seeing and taking older bucks and were supportive of
restrictions on taking young bucks. Another 35% of hunters were primarily interested in the opportunity
to take any buck of their choice and were not accepting of limitations of their opportunity. About 17%
of hunters seemed to be on both sides of the fence, supportive of accepting restrictions but also highly
valuing their freedom of choice. The final 15% were either unsure or not strongly opinionated.
In most Buck Management Zones, hunters ranked “Opportunity to Take Any Buck I Choose” slightly
higher than “Opportunity to Take a Big Buck” (see chart).
The survey did not ask directly
about hunter preferences for
various buck management
strategies, as if a vote. We tried
that in a 2010 survey, and the
results were inconclusive.
Rather, this survey focused on
hunters’ values about buck
hunting and acceptable tradeoffs.
Buck Harvest Management in New York 6
BenefitsoftheSDMApproach
SDM brought science into the decision process. Our objectives had to be clearly defined and measurable,
and alternative buck management options were assessed systematically using social and biological data.
SDM allowed us to consider hunter interests in context with management concerns, and it integrated
hunter values with likely outcomes. We tested the SDM process with small changes in the population
modeling and hunter survey data, and the outcomes remained consistent.
SDM is an adaptive process. Through our analysis, we identified several areas of uncertainty or information
gaps, then incorporated new information as needed. For example, we recognized that we initially placed
too much weight on the population management objective, considering that buck management is primarily
a social issue. So we reassessed and shifted the greatest amount of decision weight by a large margin to the
hunter satisfaction objective. Additionally, we recognized that although “freedom of choice” is a core value
for some hunters, early iterations of our SDM analysis only accounted for the relative impacts of each
management strategy on hunter opportunity and success rate. While opportunity and success may, over
time, be only slightly reduced with regulatory strategies like mandatory antler restrictions, a hunter’s
freedom of choice would remain limited. So we used data from the survey to incorporate hunter values
about freedom of choice directly into the SDM process.
ChallengeoftheSDMApproach
Because hunters have divided opinions about buck management strategies and disagree about the
importance of reducing harvest of young bucks, even with the SDM process there is no “slam dunk” option
for DEC to satisfy all New York hunters. SDM helps identify the option that best balances hunter interests.
Acknowledgments:
The structured decision‐making analysis described here was completed by Drs. Kelly Robinson and Angela
Fuller of the New York Cooperative Fish and Wildlife Research Unit at Cornell University. The deer hunter
survey was conducted by Dr. William Siemer of the Human Dimensions Research Unit at Cornell. Their work
was largely funded by the New York State Department of Environmental Conservation (DEC), using funds
made available through Federal Aid in Wildlife Restoration (Pittman‐Robertson) Grant W‐173‐G. Many DEC
staff, especially Jeremy Hurst, Art Kirsch, Jim Farquhar, Bryan Swift, Gordon Batcheller, and other members
of the Bureau of Wildlife’s Big Game Management Team, provided extensive input throughout the
development and review of this work. This helped ensure that it addressed the DEC’s need for unbiased
guidance on a very complex management issue.